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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

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68                                  ALASKAN GLACIER STUDIES
ice was still veneered with moraine, a condition which could not possibly have been the case had ablation been long active on this maze of jagged pinnacles.
The marginal lakes, and the formation and drainage of one of them, point to the conclusion that the advance was in progress; but more important than this is the fact that during our visit the ice along the glacier margin was being broken by the thrust. As we stood on Terrace Point for a few hours we heard ice falls every few minutes, and that this had been in progress for some time was proved by the presence of many white ice patches in the broken, debris-covered marginal area, caused by the recent fall of ice, and even more noticeably by the great numbers of icebergs floating in the marginal lake and stranded on the bottom of the abandoned lake.
We believe that these facts demonstrate that the advance of Lucia Glacier began no earlier than the autumn of 1908 (and probably even more recently), and that it was in vigorous progress in August, 1909. We have no reason to doubt that in a few weeks a notable difference would have been observed in the appearance of Lucia Glacier. We looked forward with the utmost interest to re-examining this glacier in 1910, for it was to be expected that great changes would take place in the interval. If they had it would have given basis for a fuller statement of the nature of the changes in these advancing glaciers than is now possible. Hitherto the advance has been nearly or completely finished when observed, but in this case there is reason for thinking that the advance, as seen in 1909, had not reached the maximum. The ideal plan, had it been possible, would have been to stay right at Lucia Glacier and record the daily changes throughout the fall and winter.
Condition in 1910. When the junior author returned to Yakutat Bay in June, 1910, he regarded the observations of Lucia Glacier as the most interesting and important which it was his privilege to undertake. On going up Yakutat Bay an enormous amount of floating ice was encountered and, as it was then apparently impossible to cross to the west side of Yakutat Bay, the investigation of the Hubbard, Nunatak and other glaciers was undertaken first, in the hope that the ice jam would thm sufficiently in the course of a week so that the west side of the bay and Lucia Glacier might then be reached.
Upon the return to outer Yakutat Bay, however, the ice jam was undiminished but three attempts were made to penetrate through the icebergs to the west side of the bay, each time without success. A camp was maintained on the east side of the bay and the ice was watched constantly for favorable conditions but each time we attempted crossing, the launch was turned back by the ice jam, after some arduous and dangerous experiences. Finally, the date of the northward-bound steamer approaching, it was necessary to choose between not seeing Lucia Glacier in 1910 or losing two weeks or a month of the season in Prince William Sound, where the author had been directed to spend most of the summer. With deepest disappointment the Lucia Glacier observations were then given up.
Such observations as could be made with field glasses from high points on the east side of Yakutat Bay revealed, however, that Lucia Nunatak had not been completely overridden and that the stagnant moraine-covered outer bulb of Lucia Glacier had not been broken up. The ice rode little, if any, higher up on the north side of the nunatak than in 1909. The crevassed glacier surface was still dark with large amounts of ablation moraine upon the serac tables. The trees upon the visible outer part of the glacier bulb were undisturbed. The Kwik River and smaller streams north of it that receive dis-